Ramiey,
I'm not quite sure why you put quotation marks around "real" unless you mean using the crown mark to denote Lindner made guns as opposed to the government using it for it's own purposes.

I have a modest accumulation of Prussian Daly's plus a file of photo's of Daly's that have interested me. After looking at both, all of the Lindner guns marked with with a "crown over crossed sidearms" have only one screw visible on the floorplate. This includes both hammerguns and hammerless.

I don't remember ever having seen the "Crown over HAL". Not saying there aren't any, I just haven't come across one.
I have seen just "HAL" or just "Crossed Sidearms" but never "Crown over HAL" If one is out there, however, I'd bet it was made in 1892.

All of of the post 1892 guns built on the A&D action have only one screw on the floorplate....even an odd ball like my Diamond Quality Hammergun with a Jones underlever and Witten steel barrels has one screw in the floorplate.
Jon